<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title>js测试</title>
    <link rel="stylesheet" href="bootstrap.min.css"/>
</head>
<body>
    <div class="dropdown">
        <button class="btn btn-default dropdown-toggle" type="button" data-toggle="dropdown">
            下拉菜单
            <span class="caret"></span>
        </button>
        <ul class="dropdown-menu" role="menu">
            <li role="presentation"><a href="#" role="menuitem" tabindex="-1">hello</a></li>
            <li role="presentation"><a href="#" role="menuitem" tabindex="-1">hello</a></li>
            <li role="presentation"><a href="#" role="menuitem" tabindex="-1">hello</a></li>
            <li role="presentation"><a href="#" role="menuitem" tabindex="-1">hello</a></li>
            <li role="presentation"><a href="#" role="menuitem" tabindex="-1">hello</a></li>
        </ul>
    </div>
    <script src="jquery-1.11.1.js"></script>
    <script src="bootstrap.min.js"></script>
    <script>
        $(document).off(".data-api");
    </script>
</body>
</html>